Time and Frequency Parameter Interactions

The relationship between time record length and resolution bandwidth for vector measurements is a natural part of the FFT Fast Fourier Transform: A mathematical operation performed on a time-domain signal to yield the individual spectral components that constitute the signal. See Spectrum. process and is common to all FFT analyzers, not just the 89600 VSA software.

The following illustration shows the measurement's range and resolution in the time and frequency domain. The arrows indicate inversely dependent parameters.

Increasing frequency Span decreases the sample period Dt (which increases the sampling rate). Also, increasing the (main or gate) time length decreases the Resolution Bandwidth (ResBW), which allows more frequency points for better resolution in a spectrum trace.